Electric fuel feed system



Nov. 21, 1933. P. s. TICE 1,935,924

, ELECTRIC FUEL FEED SYSTEM Filed Sept. 5,. 1929 2 Sheets-Sheet l d/ Z0@n l.

Nov' 21 P. S. TICE ELECTRIC FUEL FEED SYSTEM Filed sept. 5, 1929 2sheets-shank Patented Nov. 2l, 1933 UNITED STATES PATENT OFFICE ELECTRICFUEL FEED SYSTEM poration of Virginia Application September 5, 1929.Serial No. 390,602

4 Claims.

The purpose of this invention is to provide an improved construction forsupplying fuel to an internal combustion engine in which the fuel may bepumped from a fuel source to the car- 5 bureter by electrically operatedpumping apparatus mounted on the carbureter, a specific purpose of theinvention being to adapt the consti-uction to operate for supplying thecarbureter suitably for requirements of the engine regardless of thelevel of the fuel source with respect to the carbureter. Other specificpurposes are hereinafter indicated. The invention consists in theelements and features of construction shown and described as indicatedin the claims.

In the drawings:-

Figure 1 is a vertical sectional view of a construction embodying thisinvention mounted in conjunction with and structurally as a part of anengine carbureter.

'20 Figure 2 is a section at the line 2*-2 on Figure 1.

Figure 3 is a section at the line 3--3 on Figure 1.

Figure 4 is a detail portion of a sectional view of the electric motorshown in Figure 1 on an enlarged scale.

Figure 5 is an elevation of the electric motor at the end of whichFigure 4 is a section, upon the scale of Figure 4.

Figure 6 is a section at the line 6-6 on Figure 1.

Figure 7 is al section at the line '7-7 on Figure 6.

The carbureter construction shown in the drawings comprises a bodymember, A, having an air and fuel mixture conduit, 20, leading from theair inlet, 21, at which the air enters, substantially horizontally witha 90 degree bend upwardly to the upper end of said body member, at whichthe latter is adapted for mounting at the engine intake for dischargeinto the intake manifold, a choke valve, 23, being provided at theentrance, and the throttle valve, 24, being mounted at the upperdischarge end.

In the upwardly extending part of said conduit there is mounted aVenturi sleeve, 26, having formed integrally with it a nozzle member,27, hereinafter more particularly described.

The body member comprises also a fuel chamber, 30, extending adjacentthe upwardly extending part of the air and fuel mixture conduit at theside opposite the air inlet and choke valve, said chamber extending downaround and under the convex side of the 90 degree bend mentioned. 5 Thefuel chamber extending to the lower end (Cl. 10S-40) of the body member,A, is closed at that end by a bottom skeleton cap, 45, conical ingeneral form with its conical cavity at the upper side, and having amarginal exteriorly protruding flange mated in dimensions with the lowerend of the body member for clamping between said lower end of the flangeand said body member a flexible diaphragm, 47, which thereby becomeseiectively the capacity-limiting bottom of the Valve chamber; and abovesaid diaphragm is a damping plate, 48, which is a metal stamping flexedupwardly as seen at 48 at the central area within the clamped margin,48h, and insulated from the body member, A, by an interposed packinggasket, 48m- The diaphragm, 47, has at its 70 under side a sheet metaldisk, 49, reenforcing the diaphragm at a relatively large centralportion of its area, limiting its exure to the annular area, 47 1,outside said central reenforced area.

There is provided at the under side of the diaphragm a coil spring, 50,reacting between the metal disk, 49, and thereby between the daphragm,47, and an adjusting screw, 51, which is screwed into the lower end ofthe bottom cap, 45, said spring being centered at its upper end upon thenut, 6l, by which the disk, 49, is clamped to the diaphragm, the lowerend of the spring being centered upon the reduced upper end, 51, of thetensioning screw, 51.

The damping plate, 48, has a central aperture, 48d, affording restrictedaccess to the diaphragm for the fuel in the stand pipe orlever-governing chamber, 30. Said damping plate carries an insulatingpost, 48g, on the upper end of which there is secured one end of anupper contact member, 64, and below which there is secured one end of alower spring contact member, 65, said contact members both extendinginto alignment with the axis of the diaphragm where they are providedwith Contact buttons, 64a, 6521, re- 95 spectively facingeach other, thespring contact member, 65, having a nonconductive pin, 65h, projectingdown through the aperture, 48d, in the damping plate, 48, forrestricting said aperture and for encounter with the diaphragm, 47, atthe center oi the latter. The electric circuit in which theelectro-magnetic pumping device, hereinafter described, is energized,comprises a current wire indicated in Fig. 7 at 72 leading to a bindingscrew, 76, of which the threaded post, 77, is insulatedly mountedlaterally of the body, A, at the lower end thereof and protruding intothe fuel chamber, 30, closely above the damping plate, 48, as seen inFigure 1, where the terminal of said insulated binding post is inContact with the end of the spring contact member, 65, with whichcontact is maintained by the resiliency of the end portion, d, of saidcontact member which is suitably flexed for bearing against said bindingpost, as seen in Figure '7.

From the contact member, 64, the circuit is continued through aconductor, 66, hereinafter more particularly described.

From the foregoing it may be understood that in the intended operationthe accumulation of fuel in the standpipe, 30, to a predetermined degreeof hydrostatic pressure determined by the adjustment of the spring, 50,will operate the diaphragm for separating the contacts, 64a and 65,opening the energizing circuit of the electromagnetic pumping apparatus,and interrupting the fuel supply until the engine consumption causes thefuel level in the chamber, 30, to be reduced, reducing the hydrostaticpressure on the diaphragm, whose spring, 50, will thereupon react andcause the diaphragm to move the contact, 65a, for closing the circuit.

In the construction shown, the upper contactmember, 64, is a bi-metallicbar comprising two strips of metal having different co-eincients ofexpansion and contraction under temperature change, the lower striphaving the higher coeillcient so that the bar tends to be flexedupwardly at the end carrying the contact button, 64, upon rise oftemperature due to the fuel in the chamber, 30, becoming heated in therunning of the engine.

The primary purpose of this feature of the construction is to cause thehydrostatic pressure for fuel delivery to be somewhat greater when thefuel is cold than when it is hot which is desirable for the reason thata richer mixture is needed when starting with the engine, and therebythe fuel, cold, than when the engine is warmed up by running and thefuel is correspondingly heated.

In modern engines, the engine becomes heated so quickly after startingthat the normal condition may be properly considered to be the heatedcondition, and the above described features of the carbureter structuredetermining the normal depth of fuel in the carbureter fuel chamber aredesigned to ensure that depth with the engine like, causes the properlyheated condition of the engine to be obtained so quickly at the startingof the engine, that the normal condition for which the level determiningfeatures are designed, is the heated and not the cold conditions; andthe devices described get the necessary correction of level from normalto higher than normal when the engine, and thereby the fuel, is cold, orbelow what may properly be considered the normal temperature.

Accordingly, the normal form and position of the contact carrier, 64,may be considered to be its condition and form when flexed upwardly asseen in Figures 1 and 7 for holding the contact button, 64, at aposition requiring least hydrostatic pressure on the diaphragm in orderto separate the contact, 65a, from said contact, 64e. 'And the abnormalcondition may be regarded as that at which the part, 64, is straight orslightly flexed downward. y

This feature also serves a secondary, but not negligible, purposeconcerned with the increase of fluidity and reduction of viscosity whichis concurrent with rise in temperature of the fuel. By reason of theincrease of fluidity and reduction of viscosity which attend rise intemperature, the fuel will be discharged more freely, and so in greaterquantity, through a given passage which is restricted soV as to causesubstantial friction when the fuel is hot than when it is cold.

And to maintain the desired uniformity of mixture, the pressure mustdecline as the temperature rises, which is the result of making thecontact-carrying member, 64, bi-metallic, so that rise of temperaturecauses the contact button, 64a, to move in the direction for earlieropening `of the circuit, i. e., opening with less depth of fuel in thefuel chamber.

Circuit connection to the upper spring contact member, 64, is made asabove mentioned by a spring circuit wire, 66, which is mounted rigidlyin a conductive sleeve, 67, which in turn is mounted in the post, 488,above which said upper contact member is secured, the upper end of saidsleeve being peened over the contact member, 64, for securing the latteron the post as above described. Said spring contact wire extends up inthe chamber, 30, and at its upper end is bent laterally, as seen at 66h,for projecting into contact with a contact button, 80, hereinaftermentioned in the description of the electric pumping device; and forinsuring some stress of, the end of said spring circuit wire againstsaid contact button, there is provided an insulated button, 68, mountedin the wall of the chamber, 30, against 110 which the upright portion ofsaid spring circuit wire, 66, is thrust by the button, 80, in applyingand mounting the casing of the electric pumping structure hereinafterdescribed on the outside of the chamber, 30.

The chamber, 30, is interrupted at the side opposite the air inlet, 21,for a limited part of its arcuate extent around the conduit, 20, and alimited part of its vertical extent by a hollow boss, 168, whose cavityco-operates as hereinafter 120 described with the electro-magnetic fuelpump mounted on the carburetor body opposite said boss as hereinaftermentioned.

The electro-magnetic pumping element of the structure comprises asolenoid having energizing 175 circuit windings, 100, wound on anaxially hollow spool, 101, whose shaft, 101, preferably of hard brasstubing, constitutes also the piston cylinder and pumping chamber of thepump, and in which the solenoid core, 102, furnished with 130 packingrings, 103, 103, and reciprocating in the solenoid spool shaft, operatesas a piston or pumping member. At one end the spool shaft, 101, hasfitted tightly in it and forming a cylin` der head, a plate, 104, towardand from which the solenoid-core-piston, 102, reciprocates, said headcarrying an axially positioned stem, 105, on which the solenoidcore-piston slides in its reciprocation. Said stem is reduced indiameter for a substantial part of its length from the end remote fromthe head, 104, forming a shoulder, 107; and the solenoid core-piston,bored to fit said reduced part of the stem, is counterbored to nt theunreduced part, forming a shoulder, 108, which co-operates with theshoulder, A107, for stopping between said shoulders a coiled spring,110, which is normally compressed for reacting on the solenoidcore-piston, 102, to hold it spaced away from the head, 104, towardwhich it is retracted by the magnetic action when the solenoid 150winding is energized, as may be understood from the relative location ofthe middle point of the length of the wond portion of the solenoid spooland the middle point of the length of the core,

102, as seen in Figure 1.

\ The solenoid spool, 101, is fitted tightly in a cylindrical casing,111, which in turn is lfitted tightly i a cylindrical cavity, 112, ofthe main pump and'motor casing, B, said cavity being counterbored toadmit said solenoid spool casing, 111, inserted from one end of the maincasing, B, to the shoulder, 112D, formed by said counterbore The ymaincasing, B, is formed.

at the end at which the solenoid is inserted, with a flat face, 113,with which the end of the solenoid in which the head, 104, is located,is flush; and the carbureter body, A, is formed at the side opposite theair inlet, 21, with a mated face, 70, at which the cavity, 71, Yof theboss, 69, opens, and at which also the fuel chamber, 30, opens abovesaid boss,'69.

The main motor and pump casing, B, beside the cavity, 112, into whichthe solenoid spool casing, 111, is fitted, as mentioned, has at the sideopposite the at face, 113, at which it is mounted on the carbureterbody, Ya cavity, 119, partitioned from the cavity, 112, and havingproject- V'ing into it from the partitioning web, 121, a

, hollow boss, 122, whose cavity, 123, opens toward the end 'of the maincasing opposite the flat face, 113, said cavity having a closure plug,124, screwed into the boss, 122, and having a port,v125, at which thereis seated interiorly lof said plug and boss cavity, a valve, 126, ofsubstantial length and axially bored from the end opposite the valvehead to accommodate a spring, 127, which reacts upon the bottom of theboss cavity, 123, and the valve, 126, for holding the valvek normallyseated at the port, 125.

The boss cavity, 123, has communication with the fuel source, ashereinafter more particularlydescribed, by two ducts, 140, 140, formedin the casing', B, discharging 'insaid cavity by ports, 140B, 140', andieadmg up through said i'it discharge ports from the botom side of thecasing B, at which they are open for entry of the fuel from the fuelreceiving chamber hereinafter described.

The valve, 126, has a stem, 128, protruding through thevport, 125; andthe casing cavity, 119, formed widely open at the end toward which thevalve stem projects, is closed by a flexible diaphragm, 130, clamped inplace by a cover member, 131, which has an atmosphere vent, 132.

The parts are dimensioned so that atwha may be termed the normallyseated position of the valve, its stem. is thrust against the diaphragmwhen the diaphragm is at a position'due to a predeterminedsub-atmospheric pressure in the chamber.

The casing, B, is formed and arranged, ashereinafter more particularlydescribed, for fuel entrance by the two parallel ducts, 140, 140,

leading in the partition, 121, to the boss cavity, 123, in which saidducts open at opposite sides inwardly from the inner end of the plug andvalve, 126.l The casing, B, has at the lower side of the solenoidstructure a duct, 142, communicating at one end by a port, 143, with thecavity, 119, and atthe other end opening through the flat face, 113, ofthe casing, B, at which it mounted on the carbureter body as described.A port, 144, in the partition, 121, controlled by a valve, 145, leadsfrom the upper part of the chamber, 119, into the solenoid pumpcompartment, 101, at the side of 4the solenoid core-piston remote fromthe carbureter body, A; and a port, 146, controlled bya valve, 147,

leads from` said compartment to a duct, 148,

formed' in the upper part of the casing, B, leading to and openingthrough said fiat fac( of the casing. The boss, 69, of the carbureterbody has its cavity formed with two openings through the flat face, 70,of the carbureter body at which the casing, B, is mounted; the opening,1149, registers with the open end of the duct, 142, and the opening,150, provided with an inwardly opening check valve, 151, whose chamber,152, is registered with an inlet port, 153,

of the pump cylinder head, 104; said inlet port opening into thecompartment, 101", at the side of the core-piston toward the carbureterbody, A.

Beside said open port, 153, the cylinder head, 104, has a port, 155,controlled by an outwardly opening check valve, 156, said port, 153,affording fluid discharge into the carbureter fuel chamber, 30.

Upon considering this construction and arrangement of passages andvalves, it may be understood that the reciprocation of the solenoidcore-piston, 102, operates in the stroke due to the energizing of thesolenoid winding, 100,

viz., the stroke toward the mated faces of the carbureter body and thecasing, B,-to draw in fuel to the cavity, 112, by way of the port, 144,

chamber, 119, port, 125, boss cavity, 123, ports,

ber. 30.

On the reverse stroke of the solenoid core pis- `ton, fuel will be drawninto the solenoid pump compartment, 1019, past the valve, 151, throughthe cavity, 71, port, 149, duct, 142, port, 143, chamber, 119, bosscavity, 123, and ducts, 140; while fuel is discharged from the cavity,112, past the valve, 147, through the ducts, 148, into the carbureterfuel chamber, 30.

` The course of the electric circuit which includes the solenoid windingand the circuit interrupting switch for controlling the alternateenergizing and de-energizing of the solenoid windings by which thereciprocation of the piston is effected, constitute part of the subjectmatter of my pending application Serial No. 337,932, filed February 6,1928, and will require here only limited description.

, The current led in as above described from the current source by wayof the binding screw and post, 76-77, reaches the solenoid winding byway of the spring circuit wire, 66, contact button, 80, carried by thespring arm, 81, of the valve, 156, said spring arm being mountedinsulatedly on the solenoid spool head, 157, by a conductive stud, 81,whose inner end is soldered to the end of the solenoid winding at thatend of the switch, said winding having its opposite end soldered to theinner end of a conductor, 158, mountedy on the spool head, 161, inconductive contact with the free end of a short spring bar,

162, mounted by its opposite end insulatedly on the spool head on whichthere is mounted a conductive annulus, 163, with interposed insulatinggasket, 164, the spring bar, 162, being secured by one of the screws,165, which secure the annulus, 163, the latter being slotted, as seen at166, to admit theicontacting free end of the spring bar, 162, to theinsulating gasket, 164, for making the contact of the spring bar fromthe contact button, 162e, which protrudes through said insulation, sothat theconductive connection of the solenoid`winding with the annulus,163, is made through said spring bar.

A steel disk, 169, whose diameter is a little greater than the innerdiameter of the annulus, 163, is carried by three spring arms, 167, eachsecured rigidly at one end to the spool head with intervening shortposts, 168, by` which said spring arms are in conductive relation withthe annulus,

163, and at the other end secured to the steelv disk, 169, and holdingthe latter normally spaced from the annulus, so that it is in conductiverelation to thev annulus only through the spring arms, 167, which carryit resiliently with freedom of movement in both directions from normalposition.

When the solenoid core-piston makes its stroke under the reaction of thespring, 110, which occurs when thesolenoid winding circuit is open andthe circuit is ,not energized, the arrival of the solenoid core-pistoninto contact with the steel disk, 165, closes the circuit, which is thengrounded through the solenoid core and spool, tending to cause thecore-piston to be instantly retracted magnetically.

It will be seen that if the disk, 169, were positively fixed inposition, the contact of the solenoid core with it would be brokeninstantly as soon as formed by the retraction of the corepiston, and thepiston strokes would be reduced to mere trembling vibration into and outof contact with the disk.

Buty the disk being carried yieldingly and ref siliently by the springarms, 167, the momentum being flexed from normal position in theopposite direction from that in which the impact and momentum of thecore-piston first flexes them.

By this means it willbe seen that the closure g of the circuit forenergizing the solenoid is prolonged so that the piston strokes'ar'e ofsubstantial length for the pumping action.

The fuel supply is led from the fuel source through a pipe connectedwith the pump body member, B, as seen at 170, the duct, 171, in the bodymember, B, leading from they connection, 170, for discharge downwardlyas indicated aty 172 into the fuel receiving and sediment trappingchamber,` 180, consisting of a transparent cup clamped in any convenientmanner by a yoke,

181, and clamp screw, 182, onto the under side of the member, B, whichis suitably provided with an annular seat, b5," mating the upper/end ofthe cup, 180, a strainer, 185, being clamped between the cup and thebody, B, with suitable packing gaskets, 186, interposed at both sides ofthe strainer. The strainer is centrally apertured, and has its apertureflanged, as seen at 187, for engaging the boss, bs, through which theduct, 172,

discharges and registering said aperture withv said duct; and a smalldisk, 189, is mounted in any convenient manner positioned a shortdistance below the discharge of said duct, 172, for dispersing the fueldischarged downwardly to prevent it from constituting a jet which wouldstir up the sediment which may be accumulated in the bottom of the cup.

It will be understood that with this construction the fuel flowing fromthe fuel source entering the duct, 171, and delivered in the fuelreceiving chamber, 180, first lls that chamber to the top and reachesthe lower end entrance of the ducts, 140, 140, only after passingthrough the strainer, 185; so that anysolid impurities are eliminatedand prevented from entering the pump or the carbureter.. And in thisprocess the sedi ment tends to accumulate in the bottom of the cup whichcan be readily detached for removing the sediment from time to time. I

I claim:

1. An electrically operated pump having a dis charge, the pump casinghaving a chamber formm ing part of the liquid inflow conduit to thepump, a valve controlling communication of said last mentioned chamberwith the antecedent part of said conduit, said valve being arranged toseat in the direction of inflow, and a spring for holding it normallyand yieldingly seated, a flexible dia phragm forming part of the outerwall of said chamber arranged to receive the thrust of the seatingmovement of the valve, and at normal position of the diaphragm due topredetermined sub-atmospheric pressure in the chamber to hold the valveopen against the liquid inflow tending to seat it, and to yieldoutwardly and permit the valve to be seated by the pressure of theliquid in the chamber when said pressure exceeds atmospheric, thediaphragm being arranged extending up and down at one side of saidchamber and the inflow to the pump being arranged leading out from saidchamber at substantially the level of the upper margin of the diaphragm;whereby at all times during pumping operation the chamber is occupied byliquid to the depth substantially equal to the diameter of thediaphragm, and the diaphragm is thereby exposed to hydrostatic pressureof that depth of liquid over substantially its entire area.

2. The construction defined in claim l, the pump casing having anaperture closed by the diaphragm and having a chamber for the valvelocated interiorly of the first mentioned chamber opposite thediaphragm, the liquidl inflow conduit comprising a duct in the casingleading to said valve chamber, said chamber being open toward thediaphragm and having a closure plug containing the port and seat for thevalve, the valve stem being protruded from the port for cooperating withthe diaphragm for the control of the valve by the diaphragm asdescribed.

3. An electric pumping mechanism comprising a chambered casing, asolenoid structure fitted in a chamber of the casing and having areciprocating core, said solenoid and its core partitioning said chamberinto two compartments each having liquid inlet and liquid outlet, and;valves controlling the same for one-way liquid flow through therespective compartments from the liquid source to the pump discharge,said casing having at one end of the first mentioned chamber 1,93 5,924I a second chamber; a valved duct leading from the liquid source fordischarge in said second chamber, said second chamber having a iiexibledia- CTI phxiagm forming a portion of its outer wall exteriorily exposedto atmosphere and interiorly associated with the duct valve for holdingthe same open; whereby the diaphragm operates for opening the .valvecorrespondingly to the degree of yvacuum produced in the suction strokeof thesis` the valve being arranged for seating in the direc- 7 tion ofthe outward fiexure of the diaphragm.

' PERCIVAL s. TICE.

